Alistipes senegalensis is Critically Involved in Gut Barrier Repair Mediated by Panax Ginseng Neutral Polysaccharides in Aged Mice

Ginseng polysaccharides (GPs) are known to have beneficial effects on the gut epithelium and age-related systemic-inflammation through regulation of gut microbiota. However, the underlying pathways and key members of the microbial community involved in this process are poorly understood. In this study, administration of ginseng neutral polysaccharide (GPN) is found to alleviate gut leak and low-grade inflammation, concomitantly with improving the physiological function aged mice. Fecal microbiota transplantation and fecal conditioned medium are used to assess the specific involvement of gut bacterial metabolites in the effects of GPNs. Comprehensive multi-omics analyses showed that GPN significantly enriched the abundance of Alistipes senegalensis, an indole-producing commensal bacterium. Increased expression of tight junction-associated proteins, as well as activation of gut stem cells, are found to be mediated by the AhR pathway, indicating the causal mechanism by which GPN reduced increases in gut permeability. The results are verified in Caco-2/THP-1 cells, Caenorhabditis elegans, and enteroids. To the knowledge, this is the first identification of an integral functional axis through which GPN and functional metabolites of A. senegalensis influence the gut barrier and reduce systemic inflammation, providing clues for the potential development of innovative plant polysaccharide treatment strategies to promote healthy aging.